fester

 
Pronunciation: /ˈfɛstə/

verb

[no object]
  • (of a wound or sore) become septic; suppurate: (as adjective festering) a festering abscess
  • (of food or rubbish) become rotten and offensive to the senses: piles of mouldy grey paper festered by the sink
  • (of a negative feeling or a problem) become worse or more intense, especially through long-term neglect or indifference: below the surface, the old antagonisms festered
  • (of a person) deteriorate physically and mentally in isolated inactivity: remand prisoners are left to fester in our jails while they wait for trial

Origin:

late Middle English: from the rare word fester 'fistula', later 'festering sore', or Old French festrir (verb), both from Old French festre (noun), from Latin fistula 'pipe, reed, fistula'